The effect of chlorhexidine on the receptor activator of NF-êB ligand (RANKL) and osteoprotegerin (OPG) expression in chronic periodontitis in humans and companion animals

Periodontal disease is a chronic, multi-factorial disease of the
tissues supporting the teeth. Periodontitis in companion animals is an
almost identical disease to that in humans in terms of disease course
and clinical presentation.
Receptor activator of NF-B ligand (RANKL) and osteoprotegerin
(OPG) are bioactive molecules that control bone resorption. This study
aims to evaluate the effect of Chlorhexidine (CXD) on the RANKL and
OPG expressions in gingival crevicular fluid (GCF) collected from
subjects with chronic periodontitis.
GCF was obtained from subjects with chronic periodontitis.10
subjects (CXD1) rinsed the mouth with 0.12% CXD, 10 subjects (CXD2)
utilized 0.20% CXD and the last 10 (PL) used Placebo solution for 7
days. RANKL and OPG concentrations in GCF were measured by
enzyme-linked immunosorbent assays ELISA at baseline and after 7
days. Periodontal clinical variables: clinical attachment loss (CAL),
probing pocket depth (PPD), papilla-bleeding index (PBI) were
evaluated in all groups.
After 7 days in CXD1 and CXD2 group RANKL/OPG ratio exhibited
a significant decrease (p<0.05) in contrast to the PL group where
results showed similar values of RANKL/OPG ratio at baseline and after
the observation period. RANKL/OPG ratio was positively correlated with
PPD, CAL and PBI before and after the observation period in both
Chlorhexidine (CXD1, CXD2) groups.
In an existing inflammatory response, chlorhexidine reduced the
level of periodontal inflammation, which leads to reduction of
RANKL/OPG relative ratio. Decrease of RANKL/OPG ratio will
apparently induce maintenance of alveolar bone and slow down
periodontal tissue breakdown.